This book constitutes the refereed proceedings of the 19th International Conference on Formal Modeling and Analysis of Timed Systems, FORMATS 2021, held in Paris, France, in August 2021. The 8 full papers that were carefully reviewed and selected from 19 submissions are presented in this volume with 2 invited talks. The papers focus on topics such as probabilistic computation, logic and verification, robotic planning, complexity of timed pattern matching, safety violations in real-time systems, modal and temporal logics, and others.